The field of this invention is ceiling fan assemblies, and more particularly the switch unit used in ceiling fan assemblies.
Ceiling fan assemblies are often mounted in the place of existing light fittings. A ceiling fan assembly typically comprises a motor housing which is suspended from the ceiling and carries the fan blades, a switch unit which contains a switch-gear for controlling the operation of the motor, and a light fitting. The electrical connections between the motor housing and the switch unit are made by the manufacturer in a relatively permanently interconnected fashion. The apparatus is then supplied to the retailer or user with the motor housing and the switch unit already secured together and, thus, not readily disconnectible due to the nature of the electrical connections between them.
Such an assembly poses a number of disadvantages for the manufacturer or for anyone servicing the switch unit of an already-mounted ceiling fan or attempting to add or remove the light fitting of an already-mounted ceiling fan.
The fact that the electrical connections between the motor housing and the switch unit are relatively permanently interconnected prevents the switch unit from being worked on as an individual component on an assembly line, at certain stages of its manufacture, when such a technique would otherwise be desirable. For example, a worker on a production line who assembles the switch housing must manipulate the heavy motor housing at the same time. Additionally, the overall shape of the assembled motor housing and switch unit wastes space in packing and storing, thereby adding considerably to the end cost of the product.
Once the ceiling fan is mounted, an individual who wishes to service the parts inside the switch housing is forced to remove the bottom portion of the switch housing and look directly up into the interior of the housing. The individual must then work in this posture, which is particularly tiring and inconvenient. An alternative approach would be to remove the entire apparatus from the ceiling in order to service the switch unit (remembering that the motor housing and the switch unit are not designed to be readily disconnectible); however, such an alternative is clearly undesirable
If a light fitting is to be added to or removed from an already-mounted ceiling fan, the individual doing the work encounters the above-described problems in connecting or disconnecting the relevant wiring. Further, it is necessary for someone to support the weight of the light fitting at the same time, thereby, likely requiring the assistance of an additional person in the operation. Finally, adding or removing a light fitting from an already-mounted ceiling fan exposes the individual doing the work to some chance of electrical shock due to his proximity to the power source.
Additionally, an incandescent light fitting dissipates over 80% of its consumed power in the form of heat. The area just beneath the fan motor is the "eye" of the air flow vortex, similar to the eye of a typhoon or hurricane. There is very little air movement in that region, creating a potential heat build-up problem. Heat from the light fitting puts stress on the capacitor inside the switch unit which forces manufacturers to use a more expensive capacitor with a greater temperature resistance.